Stride.h

// This file is part of Eigen, a lightweight C++ template library// for linear algebra.//// Copyright (C) 2010 Benoit Jacob <jacob.benoit.1@gmail.com>//// Eigen is free software; you can redistribute it and/or// modify it under the terms of the GNU Lesser General Public// License as published by the Free Software Foundation; either// version 3 of the License, or (at your option) any later version.//// Alternatively, you can redistribute it and/or// modify it under the terms of the GNU General Public License as// published by the Free Software Foundation; either version 2 of// the License, or (at your option) any later version.//// Eigen is distributed in the hope that it will be useful, but WITHOUT ANY// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS// FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License or the// GNU General Public License for more details.//// You should have received a copy of the GNU Lesser General Public// License and a copy of the GNU General Public License along with// Eigen. If not, see <http://www.gnu.org/licenses/>.#ifndef EIGEN_STRIDE_H#define EIGEN_STRIDE_H/** \class Stride * \ingroup Core_Module * * \brief Holds strides information for Map * * This class holds the strides information for mapping arrays with strides with class Map. * * It holds two values: the inner stride and the outer stride. * * The inner stride is the pointer increment between two consecutive entries within a given row of a * row-major matrix or within a given column of a column-major matrix. * * The outer stride is the pointer increment between two consecutive rows of a row-major matrix or * between two consecutive columns of a column-major matrix. * * These two values can be passed either at compile-time as template parameters, or at runtime as * arguments to the constructor. * * Indeed, this class takes two template parameters: * \param _OuterStrideAtCompileTime the outer stride, or Dynamic if you want to specify it at runtime. * \param _InnerStrideAtCompileTime the inner stride, or Dynamic if you want to specify it at runtime. * * Here is an example: * \include Map_general_stride.cpp * Output: \verbinclude Map_general_stride.out * * \sa class InnerStride, class OuterStride, \ref TopicStorageOrders */template<int _OuterStrideAtCompileTime, int _InnerStrideAtCompileTime>
00057class Stride
{
public:
typedef DenseIndex Index;
enum {
InnerStrideAtCompileTime = _InnerStrideAtCompileTime,
OuterStrideAtCompileTime = _OuterStrideAtCompileTime
};
/** Default constructor, for use when strides are fixed at compile time */00067Stride()
: m_outer(OuterStrideAtCompileTime), m_inner(InnerStrideAtCompileTime)
{
eigen_assert(InnerStrideAtCompileTime != Dynamic && OuterStrideAtCompileTime != Dynamic);
}
/** Constructor allowing to pass the strides at runtime */00074Stride(Index outerStride, Index innerStride)
: m_outer(outerStride), m_inner(innerStride)
{
eigen_assert(innerStride>=0 && outerStride>=0);
}
/** Copy constructor */00081Stride(constStride& other)
: m_outer(other.outer()), m_inner(other.inner())
{}
/** \returns the outer stride */00086inline Index outer() const { return m_outer.value(); } /** \returns the inner stride */00088inline Index inner() const { return m_inner.value(); }
protected:
internal::variable_if_dynamic<Index, OuterStrideAtCompileTime> m_outer;
internal::variable_if_dynamic<Index, InnerStrideAtCompileTime> m_inner;
};
/** \brief Convenience specialization of Stride to specify only an inner stride * See class Map for some examples */template<int Value = Dynamic>
00098class InnerStride : publicStride<0, Value>
{
typedefStride<0, Value>Base;
public:
typedef DenseIndex Index;
InnerStride() : Base() {}
InnerStride(Index v) : Base(0, v) {}
};
/** \brief Convenience specialization of Stride to specify only an outer stride * See class Map for some examples */template<int Value = Dynamic>
00110class OuterStride : publicStride<Value, 0>
{
typedefStride<Value, 0>Base;
public:
typedef DenseIndex Index;
OuterStride() : Base() {}
OuterStride(Index v) : Base(v,0) {}
};
#endif // EIGEN_STRIDE_H